Light shutter mechanism



Jan. 27, 1942. B. s'rEcHBART 2,271,235

LIGHT SHUTTER MECHANISM Filed July 26, 1940 5 Sheets-Sheet l F1 Q. l

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LIGHT SHUTTER MECHANISM Filed July 26, 194C 5 Sheets-Sheet 4 2 INVENTUREFeuNm ETEEHEAHT @Mk ATTY Jan. 27, 1942. B. sTEcHBART 2,271,235

v LIGHT SHUTTER MECHANISM Filed July 26, 1940 5 Sheets-Sheet 5 INVENTUH'BRUNE EITEEHEAHT WMM.

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Patented Jan. 27, 1942 Lion'r 'suur'rsa MEcnANrsM Bruno Stechbart,Chicago, Ill.. assignor to The Bell & Howell Company, Chicago, Ill., acorporation of Illinois Application July 26, 1940, Serial No. 347,802

10 Claims.

My invention relates particularly to exposure shutter mechanism forphotographic cameras and involving adjustment both for light opening andexposure velocity and has for its main object the provision, with alight shutter adjustable both as to light opening and exposure velocity,of a novel, effective and convenient `shutter or exposure speedindicating means which instantly indicates the shutter or exposure speedcomprising the light opening and exposure velocity factors of theshutter.

, With this object in view, my invention consists in certain features ofnovelty in the construction, combination and arrangement of parts bywhich the said object and certain other objects, hereinafter appearing,are effected, all as fully described with reference to the accompanyingdrawings, and more particularly pointed out in the appended claims.

In said drawings- Figure 1 is a top plan view of a photographic cameraembodying my invention;

Figure 2 is a front elevation;

Figures 3, 4 and 5 are partial sectional views substantially on the line3-3 of Figure 6 land showing the mechanism in different positions ofadjustment;

Figure 6 is a sectional view substantially on the line 6-6 of Figure 3;

Figure 'l is a sectional view substantially on the line 'l-'l of Figure6; and

Figure 8 is a sectional view substantially on the line 8-8 of Figure 7.

Referring to the drawings, a camera casing is generally designated at Iand is provided with an intermediate transverse vertical partition 2forming a forward chamber 3 and a rearward chamber portion which isdivided horizontally by a horizontal transverse partition I to form anupper chamber and a lower chamber 6, the upper portion of the casingbeing formed by a separate casing portion 1 releasably secured to themain portion of the casing in a suitable manner not shown. See Figures1, 2, 6, 'l and 8. Mounted on the forward wall of the casing, is asuitable photographic lens 8 disposed on a forwardly and rearwardlyextending axis traversing the chamber 5.

The partition 2 is provided with an exposure aperture 9 coinciding withthe lens 8, and a transverse vertical film guide, generally designatedat I I, is associated with the exposure aperture 9 to position asensitized film I2 at the exposure aperture, the film being transverselymovable in the exposure guide for exposing successive portions thereof.See Figures 3 and 6.

Disposed in the rear portion or the casing below the partition 4 on aforwardly extending horizontal axis, is a usual spring motor, generallydesignated at I3, which is wound by an exterior handle III at the rearof the casing. This motor drives a multiplying spur gear train generallydesignated at I4 and which includes an intermediate gear I5 secured Aona rotatable forwardly extend-- ing shaft I6. See Figures 6, 7 and 8.

The lm I2 is disposed in the rear portion of the casing above thepartition l and, as usual, is fed from one spool, not shown, beyond oneend of the guide Il, and is wound on a spool I1 be yond the other end ofthe guide in the movement of the film through the guide for exposingsuccessive portions of the film. A revoluble vertical shaft I8, co-axialwith the spool I1 and having a usual yieldable frictional driveconnection therewith and accordingly not shown, is connected with thegear train I4 by right angle spiral gearing I9 for yieldably driving thetake-up spool with actuation of the gear train I4 by the motor I3.

Releasable stop mechanism. controlling actuation of the mechanism,consists of a bell crank lever 2l pivoted at 22 and having one endthereof projecting through a slot 23 in the lower wall of the casing forfinger actuation of the lever, a spring 24 urging the lever intostopping position, and a stop stud 25 mounted on the gear I5 andreleasably engageable with the other arm of the lever 2l to stoprotation of the gear train Il and the mechanism actuated thereby. SeeFigure 8.

Parallel guides 26 are secured in horizontal position on the upperportion of the front face of the partition 2 above and below theexposure aperture 9 and form a transversely extending slide guide. Twolight shutter members 21 and 28 are slidably mounted for independentreciprocating movement transversely across the exposure opening 9 forexposing the film thereat as hereinafter described.

Two transversely spaced generally vertical arms 29 and 3l are disposedin the forward chamber 3 and have their lower portions pivoted on thepartition 2 on transversely spaced forwardly extending axes. asdesignated at 32. See Figures 3, 6 and 7. The upper ends of the arms 29and 3l are operatively connected, respectively, with the shutter members2l and 28 for independently reciprocating the shutter members by meansof studs 33 on the shutter members and slidably and pivotally engaged inlongitudinal .slots 34 of these armsu The shaft I6 of the gear i5 isdisposed ad jacent the lower portions of the arms 29 and 3| and betweenthe same and extends forwardly into the chamber 3. See particularlyFigure 6.

A radial cam 35 is secured on the shaft I6 for rotation therewithimmediately in front of the partition 2, and asecond radialcamy 36 isrotatably mounted lon theshaft I6 immediately-in front of the cam 35.The arms 29 and 3| are independently actuated in one direction, with reAsulting corresponding movement of the shutter members 21 and 23 bytransversely disposed tension springs 31 secured with the intermediateportions of these arms and anchored on the partition 2.

A cam roller 38 is mounted on the arm 29 a short distance above thepivotal axis of this arm and is engaged by the cam 36 for actuation ofthis arm in opposition to the spring 31 of this arm, and a cam roller 39is mounted on the arm 3| a short distance from the pivotal axis of thisarm and is engaged by the cam 35 for actuation of this arm in oppositionto the spring 31 of this arm.

The opposing vertical edges 4| of the shutter members 21 and 28 haveabutting relation and are shouldered as shown for excluding the passageof light therebetween when in abutting relation, as shown in Figure 3,and, when the shutter members are separated in their relativereciprocable movement, the edges 4| form an exposure opening forexposing the portion o! the nlm at the exposure aperture 9, whichexposure opening is variable by relative movement of the shutter membersin their reciprocable movement.

The cams 35 and 36 are driven in adjustable timed relation in thefollowing manner, this phase of the present disclosure being thesubjectmatter of my co-pending U. S. application for Letters Patent,Serial Number 321,252, filed Feb ruary 28, 1940, for improvement inLight shutter.

The cam 36, which is rotatable on the shaft I6, is provided with a spurgear 42, and a spur gear 43 o! the same diameter as the gear 42 issecured on the shaft |6. See Figures 3 to '7 inclusive. An idler spurgear 44, of larger diameter than the gears 42 and 43, is rotatablymounted on the shaft I6, and a counter gear member, comprising a smallspur gear 45 and a large spur gear 46, is rotatably mounted, asdesignated at 41, on a vertical transversely extending plate 43 securedwith the casing in the chamber 3, and has the gear 45 meshing with thegear 44 and the gear 46 meshing with the gear 43.

A bored disk 49 is rotatably mounted on the shaft I6, and a boredcounter gear member, comprising a small spur gear and a large spur gear52, is rotatably mounted, as designated at 53, on the disk 49 forangular adjustment with the disk on the axis of the shaft I6, and hasthe gear 5| meshing with the gear 44 and the gear 52 meshing with thegear 42.

Thus a gear train drive is provided for driving the cams 35 and 36 intimed one-to-one relation, angular adjustment of the disk 49 resultingin adjustment of the timing o! the cams and consequent adjustment of theexposure or light opening formed by the shutter members 21 and 23, asfully described in my aforesaid application for U. S.Letters Patent.

The disk 49 is adjusted from the exterior of the camera by means of anangular-1y movable Cil 4anisrn,theyshutter members 21 and 28 areactuated from their starting position,l as shown in Figure 3, in timedspaced relation to effect exposure and are then actuated in the oppositedirection in abutting light interrupting relation to return them totheir starting position, the nlm being actuated, by means not shown,during suchi return movement to position an unexposed portion thereof atthe exposure aperture 9 preparatory to another exposure cycle of theshutter membersi A centrifugal speed governor of usual construction, seeFigures 7 and 8, is driven from the gear train I4 by means of spiralgearing 60 and comprises rotatable centrifugal weight means 6| Vdrivenfrom the gear 'train I4, a rotatable axially movable brake disk 62 alsodriven from the gear Ytrain |4 and axially controlled by the weightmeans 6|, and a non-rotatable brake element 63 frictionally engageablewith the brake disk in opposition to axial actuation of the brake diskby the weight means and mounted on a carrier member 64 slidably mounted,as designated at 65, to adjustably position the brake element 63 axiallyof the brake disk 62 for adjusting the governor controlled speed of themechanism and consequently adjustably varying the exposure velocity ofthe shutter members 21 and 28. A rotatable shaft 66, disposed on ahorizontal forwardly extending axis, is provided with a gear segment 61which meshes with a rack 63 on the carrier member 64 for adjusting thecarrier member.

A rotatable shaft 69, disposed on a horizontal forwardly extending axis,has fixed therewith a radial cam 1| provided with three angularly spaceddwell portions 12, 13 and 14 of different radii, and an arm 15 issecured on the shaft 66 and is maintained in engagement with the cam 1|by a spring 16, so that the cam 1| is operative, through the arm 16, theshaft 66, and the gear segment 61 meshing with the rack 6l, to adjustthe carrier member 64 and brake element 63 for adjusting the speed ofthe mechanism and consequently the exposure velocity of the lightshutter, each of the dwell portions 12, 13 and 14 representing apredetermined exposure velocity. See Figures 3, 4, 5, 6 and 1. The shaft69 is adjusted from the exterior of the camera by a rotatable knob 11secured on this shaft, suitable scale and index means, generallydesignated at 18, being associated with this knob for indicating theshutter exposure velocity.

An arm or actuating member 19 is pivotally mounted on the shaft 69 forpivotal movement on the axis thereof, and an indicating arm Il has theintermediate portion thereof pivotally mounted on the arm 19 on an axisparallel in the pivotal axis of the arm 19 and of the shaft 69, asdesignated at 32. One end of the arm 3| is provided with an angularlyextending shutter or exposure speed indicating scale 83, which lies onthe inside of and traverses, in the movement of this arm, a restrictedwindow 34 in the front wall of the casing to be visible at the window,the restricted window forming an index for the scale to indicate theshutter or exposure 12, 19 and .14 of the cam 1I, so that asthe cam 1Iis positioned to engage one of its dwells with the arm 15, thuseffecting the corresponding shutter velocity adjustment, thecorresponding dwell of the cam 85 engages the arm 8| to ling disk 49 isprovided with a radial cam 9| which is engaged by the arm 19 forpivotally adjusting this arm in correspondence with the light opening ofthe shutter, the spring 85 serving to maintain the arm 19 in engagementwith the cam 9|. Adjustment of the arm 19 on its pivotal axis eiectscorresponding adjustment of the pivotal mounting 82 of the armv8|, sothat the arm 8| is thus adjusted for indication with reference to theinstant light opening of the shutter.

Th cam 85 operating on the arm 8|, and the cam 9| operative on thepivoted arm 19 operating in `conjunction with the pivotal mounting 82 ofthe arm 8| on the arm 19, operate in parallel mutually reactive relationfor positioning the arm 8| in accordance with both the instant lightopening of the shutter and with the instant exposure velocity of theshutter, thus conveniently indicating the shutter or exposure speedinvolving both of these factors.

Figures 3, 4 and 5 show the mechanism in different adjustments thereof,the arm 8| being engaged with the intermediate dwell 88 of the shuttervelocity indicating cam 85 in Figures 3 and 4 and with the highest dwell89 of the cam 85 in Figure 5, and the arm 19 being positioned in thesame position by the shutter opening indicating cam 9| in Figures 3 and5 and in another position in Figure 4, resulting in correspondinglydifferent shutter or exposure speed indications by the scale 89 of thearm 8|. In the construction shown', adjustment of the shutter lightopening which adjusts the arm 19 on the pivotal axis of the cam 85 doesnot cause pivotal movement of the arm 8| on its pivotal axis 82, the arm8| merely moving along the engaged dwell 81, 88 or 89 of the cam 85.

While I have thus described my invention, I do not wish to be limited tothe precise details described, as changes may be readily made withoutdeparting from the spirit of my invention, but having thus described myinvention, I claim as new and desire to secure by Letters Patent thefollowing.

I claim:

1. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter,adjustable means for varying the exposure velocity of said shutter, amovable shutter speed indicating member, and two means respectivelyunder the control oi' said light opening and exposure velocity varyingmeans and Y'3 operatively eennected with seid indiening memper inparallel mutually reactive relation for positioning said indicatingmember to indicate the instant shutter speed.

2. In alight shutter mechanism, the combination with a light shutter, ofadjustable means `for varying the vlight opening oi said shutter,adjustable means for varying the lex posure velocity of said shutter. amovable shutter speed indicating member, and two means respectivelyunder the control of 'said light opening and exposure velocityvaryingmeans and including a pivotal connection with said indicatingmember and operatively connected with said indicating member in parallelmutually reactive relation for positioning said indicating memberVtoindicate the instant shutter speed.

3. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter,adjustable means for varying the exposure velocity of said shutter, amovable, shutter speed indicating member, and means under the control ofsaid light openingl and exposure velocity varying means and operative onsaid indicating member to indicate'the instant. shutter sped comprisingmovably mounted actuating means under the control of one of saidadjustable means, an operative connection between said indicating memberand said actuating means permitting independent movement of saidindicating member with reference to said actuating means. and a secondactuating means under the control of the other of said adjustable meansand operative on said indicating member with reference to saidindependent movement thereof.

4. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter,adjustable means for varying the exposure velocity of said shutter, amovable shutter speed indicating member, and means under the control ofsaid light opening and exposure velocity varying means and operative onsaid indicating member to indicate the instant shutter speed comprisinga pivotally mounted actuating member under the control of one of saidadjustable means, a pivotal mounting carrying said indicating member onsaid actuating member for pivotal movement with reference thereto on anaxis parallel to the pivotal axis of said actuating .i

member, and additional actuating means under the control of the other ofsaid adjustable means and operative to actuate said indicating member onits pivotal mounting.

5. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter,adjustable means for varying the exposure velocity of said shutter, amovable shutter speed indicating member, and means under the control ofsaid light opening and exposure velocity varying means and operative onsaid indicating member to indicate the instant shutter speed comprisinga pivotally mounted actuating member under the control of one of saidadjustable means, a pivotal mounting carrying said indicating member onsaid actuating member for pivotal movement with reference thereto on anaxis parallel to the pivotal axis of said actuating member, and anangularly movable radial cam under the control of the other of saidadjustable means and disposed on the pivotal axis of said actuating 8.In alight shutter mechanism, the combinamember and operative on saidindicating memtion with a light shutter. of adjustable means for varyingthe light opening ot said shutter, adjustable means for varying theexposure velocity of said shutter, a movable shutter speed indicatingmember, and means under the control of said light opening and exposurevelocity varying means and operative on said indicating member toindicate the instant shutter speed comprising a pivotally mountedactuating member, a pivotal mounting carrying said indicating member onsaid actuating member for pivotal movement with reference thereto on anaxis parallel to the pivotal axis of said actuating member, an angularlymovable radial cam under the control of one oi said adjustable means anddisposed on an axis parallel to the pivotal axis oi said actuatingmember and operative thereon, and a second angularly movable radial camunder the control oi the other oi' said adjustable means and disposed onthe pivotal axis of said actuating mem,- ber and operative on saidindicating member.

'1. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter,adjustable 'means for varying the exposure velocity oi said shutter, oneof said adjustable means including an angularly movable adjustingmember, a movable shutter speed indicating member, and means under thecontrol of said light opening and exposure velocity varying means andoperative on said indicating member to indicate the instant shutterspeed comprising an actuating member pivotally mounted on the axis oi.'said adjusting member and under the control of the other of saidadjustable means, a pivotal mounting carrying said indicating member onsaid actuating member for pivotal movement with rei'- erence thereto onan axis parallel to the pivotal axis of said actuating member, andadditional actuating means under the control of said adjusting memberand operative to actuate said indicating member on its pivotal mounting.

8. In a light shutter mechanism, the combination with a light shutter,of adiustable means for varying the light opening oi said shutterincluding an angularly movable adjusting member, ad-

justable means for varying the exposure velocity of said shutterincluding a second angularly movable adjusting member disposed on anaxis parallel to that oi said ilrst mentioned adjusting member, amovable shutter speed indicating member. and means under the control oisaid llsht opening and exposure velocity varying means and operative onsaid indicating member to indicate the instant shutter speed comprisingan actuating member pivotally mounted on the axis of one of saidadjusting members, a radial.

cam on the ,other of said adjusting members for actuating said actuatingmember, Ia. pivotal mounting carrying said indicating member on saidactuating member for pivotal movement with reference thereto on an axisparallel to the pivotal axis oi said actuating member, and a secondradial cam on said one adjusting member and operative on said indicatingmember to actuate the same on its pivotal mounting.

9. In a light shutter mechanism, the combination with alight shutter, oiadjustable means for varying the llight opening ci said shutter. ad-Justable "means for varying the exposure velocity of said shutter, amovable shutter indicating member, and means under the control oi saidlight opening and exposure velocity varying means and operative on saidindicating member -to indicate the instant shutter speed comprising apivotally mounted actuating member under the control of one of saidadjusting means, a pivotal mounting carrying said indicating member onsaid actuating member for pivotal movement with reference thereto on anaxis parallel -to the pivotal axis of said actuating member, and anangularly movable radial cam co-axial with the pivotal axis of saidactuating member and under the control of the other of said adjustablemeans and operative on said indica-ting member and provided with aplurality of angularly spaced dwell portions oi different radii.

10. In a light shutter mechanism, the combination with a light shutter,of adjustable means for varying the light opening of said shutter, adjustable means i'or varying the exposure velocity of said shutter, amovable shutter indicating member, and means under the control oi.' saidlight opening and exposure velocity means and operative on saidindicating member to indicate the instant shutter speed comprising apivotally mounted actuating member, a pivotal mounting carrying saidindicating member on said actuating member for pivotal movement withreierence thereto on an axis parallel to the pivotal axis of saidactuating member, an angularly movable radial cam co-axial with thepivotal axis of said actuating member and under the control of saidexposure velocity means and operative on said indicating member andprovided with a plurality of angularly spaced dwell portions of`different radii, and a second angularly movable radial cam disposed onan axis parallel to that of said first mentioned cam and under thecontrol of said light opening varying means and operative on saidactuating member.

BRUNO STECHBART.

